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)

While voluntary movement blocks Parkinsonian rest tremor (PT), essential tremor (ET) is enforced by postural and/or kinetic action. We studied the effect of contralateral externally- and internally triggered hand movement on PT and ET to investigate the transhemispheric influences on tremor genesis. We measured the changes of tremor peak frequency power after flash signal (F), flash triggered (FM) and self-paced (SPM) movement of the contralateral hand in nine PT and seven ET patients using accelerometer. PT significantly decreased both during FM and SPM tasks, suggesting that it is generated by a constant subcortico-cortical network, which includes higher order motor areas. Intensity of ET showed a remarkable intra- and interindividual variability both during FM and SPM reflecting a different generator circuitry with variable functional connections.
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PMID:Contralateral voluntary hand movement inhibits human parkinsonian tremor and variably influences essential tremor. 1500 81

Development of the new radiopharmaceuticals and the statistical analysis techniques for the brain SPECT were reviewed. Both 123I-beta-CIT and 123I-FPCIT SPECT demonstrate the neuronal degeneration of the presynaptic dopaminergic system. The preclinical trials are on-going for the differentiation between essential tremor and Parkinsonian patients. 123I-iomazenil was approved by the Japanese Minister of Health, Labour and Welfare in Aril 2004, only for the use of epileptic patients considered surgical treatment. Both SPM and 3D-SSP are powerful techniques for statistical analysis of the brain perfusion SPECT. They are helpful for the detection of the functional alteration in neurodegenerative disorders, and useful for the differentiation between the Parkinsonian patients, including PD, MSA, PSP and CBD. Hypoperfusion in the posterior cingulated cortex can be also easily demonstrated by these techniques in Alzheimer's disease. 3D-SRT is a technique using the anatomical standardization and ROI template consisting 636 ROIs for the whole brain. Although this technique was originally developed for the evaluation of the acetazolamide test, it can be used for the evaluation of the perfusion pattern in neurodegenerative disorders.
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PMID:[Advance of SPECT: differential diagnosis and evaluation of pathophysiology of neurodegenerative disorders]. 1565 24

This study set out to determine whether there is white matter involvement in essential tremor (ET), the most common movement disorder. We collected diffusion MRI and analysed differences in fractional anisotropy (FA) and mean diffusivity (MD) between ET patients and control subjects as markers of white matter integrity. We used both classical ROI-based statistics and whole-brain analysis techniques, including voxel-wise analysis with SPM5 and tract-based spatial statistics (TBSS). Using region of interest (ROI) analysis, we found increased MD bilaterally in the inferior cerebellar peduncles (ICP) and reduced FA in the right-sided ICP of ET patients. Whole-brain analyses with TBSS detected increased MD distributed in both motor and nonmotor white matter fibers of ET patients predominantly in the left parietal white matter, while there were no significant FA differences in these areas between ET patients and controls. Voxel-wise analysis with SPM detected significant increase of MD congruent with the highest probability of difference as detected by TBSS. VBM analysis of T1 images did not detect significant differences in either gray or white matter density between our study groups. In summary, we found evidence for changes in white matter MRI properties in ET. The circumscript pathology of the ICP corroborates the pathogenetic concept of the cerebellum and its projections as key structures for tremor generation in ET. Moreover, increased diffusivity in white matter structures of both hemispheres suggests widespread alterations of fiber integrity in motor and nonmotor networks in ET patients. The underlying cause of the DTI changes observed remains to be elucidated.
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PMID:Diffusion tensor imaging of white matter involvement in essential tremor. 2057 9