Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Regional cerebral blood flow was assessed in 19 patients with early idiopathic Parkinson's disease (PD) and 12 control subjects of similar age by single-photon emission tomography using technetium-99m hexamethylpropylene amine oxime (HMPAO). Of the patients with PD, seven were mildly demented and 15 presented with hemiparkinsonism. Mean HMPAO cortical or basal ganglia/cerebellum activity ratios were calculated. Mean cortical and regional uptake ratios in non-demented PD patients were not significantly different from values in the controls. In contrast, besides generalized cortical hypoperfusion, demented PD patients had significantly lower HMPAO uptake in the frontal and basal ganglia regions than non-demented patients. These observations support the hypothesis of impaired neuronal activity in both cortical and subcortical regions of the brain in demented PD patients. In hemiparkinsonian patients, the only asymmetrical finding was a relative hypoperfusion in the contralateral parietal region. This may be due to deafferentation of the thalamoparietal pathways. The lack of asymmetrical uptake in basal ganglia in our PD patients may be explained by their staging at the time of the investigation (stage I and II, Hoehn and Yahr scale).
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PMID:Technetium-99m hexamethylpropylene amine oxime single photon emission tomography of the brain in early Parkinson's disease: correlation with dementia and lateralization. 849 Dec 27

Signs of attentional dysfunction mimicking spatial neglect have been described both in humans with lateralised Parkinson's Disease (PD) and in animals with MPTP-related hemiparkinsonism. Such deficits have been attributed to dopamine loss in basal ganglia and cortical targets. However, in previous studies the existence of neglect was assumed from behavioural tests which needed a motor output, thus entailing interpretation ambiguities due to effects of directional hypokinesia. We recorded brain event-related potentials (ERPs) evoked by the presentation of target somatic stimuli to the affected and non-affected sides in 44 patients with unilateral or asymmetrical PD. The N2 and P3 ERP components were specifically analysed, since (a) they are triggered selectively by task-relevant, attended sensory stimuli; (b) their latency reflects stimulus evaluation time, independently from the execution of a motor response, and (c) they have proved to be abnormal in hemineglect syndromes due to focal brain lesions. Irrespective of the side (left or right) of motor symptom predominance there were no significant ERP differences to stimulation of the affected and non-affected limbs, nor was there any correlation between ERP latencies and the degree of dopamine-related motor impairment. The P3 latency was abnormally delayed in 23% of the patients, but there was no trend for abnormalities to concentrate on the affected side. This study does not confirm the existence of a significant attentional impairment toward the affected limb in lateralised PD, and suggests that previous clinical evidence of "neglect' behaviour in PD might be linked to directional hypokinesia, thus reflecting intentional, rather than attentional lateralised deficits.
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PMID:Brain responses to detection of right or left somatic targets are symmetrical in unilateral Parkinson's disease: a case against the concept of "parkinsonian neglect'. 895 46

Recently, we demonstrated amelioration of behavioral deficits associated with 6-hydroxydopamine-induced hemiparkinsonism by transplanting rat testis-derived Sertoli cells into adult male rat brains. In the present study, we used adult female hemiparkinsonian rats to investigate whether the beneficial effects of transplantation of Sertoli cells may be differentially affected by gender of the animal transplant recipient. At 1 month posttransplantation, animals transplanted with Sertoli cells showed functional recovery as revealed by significant reductions in apomorphine-induced rotational behavior and asymmetrical elevated body swing behavior. Control animals that received medium alone did not display any visible behavioral recovery. These results suggest that transplantation of Sertoli cells is not male hormone-dependent and further support the use of these cells as a graft source for Parkinson's disease and other neurological disorders.
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PMID:Intracerebral transplantation of testis-derived sertoli cells promotes functional recovery in female rats with 6-hydroxydopamine-induced hemiparkinsonism. 939 81

We described the clinical and neuroradiological findings together with a transcranial magnetic stimulation study in two patient with hemiparkinson-hemiatrophy syndrome (HP-HA). In both patients the neuroradiological findings (MRI) and the central motor conduction were normal whereas the functional imaging studies (SPECT) showed asymmetrical perfusion in the basal ganglia; the intracortical inhibition at short interstimulus intervals and the silent period duration in the motor cortex contralateral to hemiparkinsonism were significantly increased only in one of the patient which has a poor response to L-Dopa therapy. These studies suggest that intracortical or thalamo-cortical neuronal inhibition may be increased in HP-HA. The etiopathogenetic considerations, the diagnostic criteria and the prognostic value of our finding to evaluate the clinical evolution of parkinsonism are discussed in the context of current models of basal ganglia-thalamo-cortical connectivity. Transcranial magnetic stimulation will provide valuable information for the differential diagnosis of the parkinsonian disorders and may predict the efficacy of L-Dopa therapy.
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PMID:Hemiparkinson-hemiatrophy syndrome: a transcranial magnetic stimulation study. 1283 89

Hemiparkinsonism-hemiatrophy syndrome (HPHA) is a rare form of parkinsonism, characterized by unilateral parkinsonism, ipsilateral body atrophy and early age of onset. We report a 59-year-old woman with hemiatrophy of her face and upper limb on the left side presenting progressive hemiparkinsonism. Most of the HPHA patients have early age of onset, however, HPHA patients with age of onset over 50 years old have been reported. The clinical features of CBD are partly similar to those of HPHA, therefore it is important to consider HPHA as differential diagnosis of CBD even if the onset is late. In our patient, hemiatrophy was useful to differentiate HPHA from CBD. In previous reports, there was a difference between the dopamine D2 receptor binding capacity of CBD and that of HPHA. While the dopamine D2 receptor binding capacity of CBD was decreased asymmetrically, that of HPHA was not decreased. The PET finding of our patient revealed that asymmetrical reduction of [11C]-CFT uptake, meaning unilateral dopaminergic presynaptic hypofunction. However, [11C]-raclopride uptake, which assesses dopamine D2 receptor binding capacity, was normal. These PET findings are consistent with previous reports on HPHA. In our patient, hemiatrophy and PET findings were useful to diagnose HPHA.
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PMID:[Late onset hemiparkinsonism-hemiatrophy syndrome: a case report]. 1596 Jan 80

Controversy exists as to whether muscle weakness is present in Parkinson's disease (PD). Computerized literature searches identified clinical trials and reviews about muscular strength assessment in patients with Parkinson's disease, using the following databases: PubMed, Ovid MEDLINE, Ovid EMBASE, the Cochrane Database of Systematic Reviews, Cumulative Index to Nursing and Allied Health Literature, and Physiotherapy Evidence Database. Seventeen articles fulfilled all criteria for selection. These studies suggested that isokinetic muscle strength was decreased in patients with Parkinson's disease and that muscle weakness was not specifically related to tremor or rigidity. Bilateral asymmetrical muscle weakness was present in Parkinson's disease when presenting with clinical unilateral hemiparkinsonism. Recent studies using sensitive mechanical devices have provided evidence that muscle strength is reduced in patients with Parkinson's disease compared with age-matched controls. The specific cause of this weakness is not known. Questions under debate were whether this weakness was of central or peripheral origin and whether it was intrinsic to the disease or a secondary phenomenon.
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PMID:Is there muscular weakness in Parkinson's disease? 1948 24

Parkinson's disease and experimentally induced hemiparkinsonism are characterized by increased beta synchronization between cortical and subcortical areas. This change in beta connectivity might reflect either a symmetric increase in interareal influences or asymmetric changes in directed influences among brain areas. We assessed patterns of functional and directed connectivity within and between striatum and six cortical sites in each hemisphere of the hemiparkinsonian rat model. LFPs were recorded in resting and walking states, before and after unilateral 6-hydroxydopamine lesion. The hemiparkinsonian state was characterized by increased oscillatory activity in the 20-40 Hz range in resting and walking states, and increased interhemispheric coupling (phase lag index) that was more widespread at rest than during walking. Spectral Granger-causality analysis revealed that the change in symmetric functional connectivity comprised profound reorganization of hierarchical organization and directed influence patterns. First, in the lesioned hemisphere, the more anterior, nonprimary motor areas located at the top of the cortical hierarchy (i.e., receiving many directed influences) tended to increase their directed influence onto the posterior primary motor and somatosensory areas. This enhanced influence of "higher" areas may be related to the loss of motor control due to the 6-OHDA lesion. Second, the drive from the nonlesioned toward the lesioned hemisphere (in particular to striatum) increased, most prominently during walking. The nature of these adaptations (disturbed signaling or compensation) is discussed. The present study demonstrates that hemiparkinsonism is associated with a profound reorganization of the hierarchical organization of directed influence patterns among brain areas, perhaps reflecting compensatory processes.SIGNIFICANCE STATEMENT Parkinson's disease classically first becomes manifest in one hemibody before affecting both sides, suggesting that degeneration is asymmetrical. Our results suggest that asymmetrical degeneration of the dopaminergic system induces an increased drive from the nonlesioned toward the lesioned hemisphere and a profound reorganization of functional cortical hierarchical organization, leading to a stronger directed influence of hierarchically higher placed cortical areas over primary motor and somatosensory cortices. These changes may represent a compensatory mechanism for loss of motor control as a consequence of dopamine depletion.
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PMID:Alterations in Functional Cortical Hierarchy in Hemiparkinsonian Rats. 2868 5